Combined refrigerating and defrosting system



Feb. 21, 1961 F. RICHELLI ETAL 2,972,238

COMBINED REFRIGERATING AND DEFROSTING SYSTEM Filed Jan. 27, 1958 3Sheets-Sheet 2 INVENTOR. ZFEIDERICO PICH'ELL! =+LReoo W: GSA/FR Feb. 21,1961 F. RXCHELLX ETAL 2,972,238

COMBINED REFRIGERATING AND DEFROSTING SYSTEM Filed Jan. 27, 1958 9 3Sheets-Sheet 3 INVENTOR.

FEm-tmco R m! M'FREDO WIGSA/ER United. States. Patent COMBINEDREFRIGERATING AND DEFROST- IN G SYSTEM Federico Richelli, Milan, andAlfredo Wiesner, Rome,

Italy, assignors to A.I.F.E.L;-Apparecchiature Industriali Frigorifere eLattiere Societa per Azioni, Rome, Italy Filed Ian. 27, 1958, Ser. No.711,404

Claims priority, application Italy Ian. 26, 1957 4 Claims. (Cl. 62-262)The present invention relates to a combined refrigerating and defrostingsystem which utilizes externally located evaporators for refrigeratedrooms. In known types of refrigerated rooms cooled by externally locatedevaporators, the latter are usually defrosted by causing a periodicalflow of relatively warm external air through the evaporator coils tothus bring about a defrosting of the same.

Hitherto, the casing of such externally located evaporator coils wasusually connected to the refrigerated room by conduits and insulateddoors were provided so as to allow the closing of for conduits from andto the refrigerated room and the opening for access and exit of thewarmer external air through the evaporator coils.

However, the operation of such doors was rather complex, impractical andtoo troublesome to be suitable for actuating them automatically.

These and other disadvantages are overcome by the system constructed inaccordance with the present invention, which allows for periodicalpassage of warmer external air through the evaporator coils and whichmay be actuated by extremely simple means so as to be suitable forautomatic operation as well.

The system constructed in accordance with the present invention ischaracterized in that the evaporator is contained in an insulated casingdisplaceable toward or from a window in the insulated wall of therefrigerated room.

The casing has an open side facing the Window and is rigidly connectedwith a stopper plate located at the inner side of the window formed inthe wall of the refrigerated room.

Thus, by moving the evaporator casing toward the window frame in thewall of the refrigerated room the evaporator is brought into contactwith the air in the refrigerated room because the stopper plate issimultaneously moved away from the window whereby the refrigeratingcycle can take place.

By moving the evaporator casing away from the window in the wall of therefrigerated room, the stopper plate will close the window from theinside and the evaporator coils will be exposed to the flow of warmerair arriving from outdoors through the clearances formed between theevaporator casing and the wall of the refrigerated room.

The casing is provided with a blower to bring about a forced flow of airthrough the evaporator coils either during the defrosting cycle orduring the refrigerating cycle while the means for moving the evaporatorcasing can be controlled manually or automatically.

The system of this invention is capable of many modifications, both withregard to the displacement of the evaporator casing to and from therefrigerated room, and also with regard to the arrangement of thevarious parts.

Only by way of example, two embodiments will be now described withreference to the accompanying drawings, wherein:

Figs. 1 and 2 are similar sectional views of one embodimcnt comprising adevice for displacing the evaporator casing toward and away from therefrigerated room by 2,972,238 Patented Feb. 21, .1961

moving the casing along a curved path, Fig. 1 showing the evaporator inoperative position and Fig. 2 in the position during defrosting.

Figs. 3 and 4 illustrate a device for rectilinearly displacing of theevaporator casing with respect to the refrigerated room intorefrigerating position and the position in which the evaporator isdefrosted, respectively.

Fig. 5 is a front elevational view of the evaporator casing and of asupporting frame therefor, the frame also serving as a support for thecondensing unit reciprocable in the manner as shown in Figs. 1 and 2.

' Fig. 6 is a vertical section taken along line 66 of Fig. 5 as seen inthe direction of arrows.

With reference to the embodiment shown in Figs. 1 and 2, 1 is a wall ofthe refrigerated room a, 2 the casing of the evaporator 3, and 5 is aprojection or extension of the casing supporting the stopper plate 5'and passing through the window 4 in the wall 1. The open side of casing2 faces the wall 1.

According to this embodiment, the frame 2' supporting the casing 2 ispivoted at 6 and is designed to contain the condensing unit, while thehollow casing 2 contains the evaporator 3 and the blower 8 which latterforces the air through the coils of the evaporator 3.

Blower 8 is driven by motor 9. As is shown in Figs. 5 and 6, the frame2' supports conventional parts such as a compressor 10, driven by motor11, and connected to an air-cooled condenser 12 and a water cooledcondenser 12', which can be designed so as to operate simultaneously orseparately.

In the refrigerating position, which is that shown in Figs. 1 and 6, theair flow induced by the blower 8, after passing through the evaporatoris returned into the refrigerated room a through the open side of thecasing 2 and the window 4 as is indicated by arrows X.

When it becomes necessary to defrost the evaporator 3, the casing isbrought into the position shown in Fig. 2. To attain this result, acrank type system 14 is provided, this system being pivotally connectedat one end 15 to the wall 1, and at the other end to an eccentric 16,actuated by the motor 17.

In the position of Fig. 2, the stopper plate 5' completely closes thewindow 4 of the refrigerated room a, and the evaporator 3 communicatesnow with the surrounding atmospheric air through the clearances orpassages 18 formed between wall and casing as shown by arrows X with theresult that the evaporator 3 is rapidly defrosted.

Of course, instead of a crank drive, a telescopic device could beadopted, for instance one consisting of a cylinder with piston and apiston rod, using a hydraulic or pneumatic drive.

Figs. 3 and 4 illustrate a slight modification of the inventionaccording to which the evaporator casing is displaceable between anoperative position (Fig. 3) and a position in which the evaporator unitis ready for defrosting (Fig. 4). The extension 5 which constitutes ameans for connecting the casing 2 with the stopper or sealing plate 5 isslidably received in the window 4 and thus guides the assembly or" parts2, 3, 5, 8 and 9 between the positions of Figs. 3 and 4. The means forreciprocating the assembly between such positions is not illustrated asit may be similar to that shown in Figs. 1 and 2.

Though only two embodiments of the device constructed in accordance withthe present invention have been described, it will be apparent to thoseskilled in the art that many additional constructional variations arepossible without departing from the scope of the appended claims.

What we claim is:

1. A combined refrigerating and defrosting system comprising arefrigerated room having a wall formed withrarwindow; a hollow casingexternally adjacent said 7 open side and said window and, the casingforming with said wall at leastione passage connecting its interior withthe surrounding atmosphere through said open side when the casing is insaid second position; an evaporator in said casing for cooling theinterior of said room when the casing is in said first position anddefrostable by atmospheric air when the casing is in said secondposition; and a stopper plate connected to said extension in said roomand spaced from said window when the casing is in said first position toform with the wall at least one air passage between said room and saidevaporator by way of said window and said open side whereby theevaporator cools the interior of said room, and the plate abutting saidwall to seal the window from the interior of said room when the casingis moved into said second position.

2. The structure as set forth in claim 1. further com- I, prising meansfor reciprocating the casing and the stopper plate to movements in asubstantially rectilinear path between said first and second positions.

3. The structure as set forth in claim 1, further comprising asupporting frame having one end fixed to said casing, another end, andpivotable with said casing about said last mentioned end in directionsto move the casing between said first and second positions; and meansoperating between said wall and said frame for pivoting the latter aboutsaid last mentioned end.

4. The structure as set forth in claim}, wherein said means comprises amotor carried by said frame; an eccentric operatively connected to androtatable by said motor; and crank means operatively connected with saideccentric and swingably fixed to said wall for pivoting the casingbetween said first and second positions when the eccentric is rotated'by said motor.

References Cited in the file of this patent UNITED STATES PATENTS2,433,655 Di Zoppola Dec. 30, 1947 2,436,713 Cody Feb. 24, 19482,525,868 Corhanidis Oct. 18,1950 2,647,376 Carlsson Aug. 4, 19532,717,508 Loveley Sept. 13, 1955 udvumm

